The invention relates to internal combustion engines, and, more particularly, to cam following roller apparatus for internal combustion engines. Even more particularly, the invention relates to roller apparatus following a cam attached to a timer plate and operably connected to a throttle valve for actuation thereof.
It is known to use plastic rollers which rotate about a pin and which have rolling contact with a cam surface. These plastic rollers reduce friction between the cam surface and the cam follower. However, such plastic rollers tend to wear out due to abrasion from friction.
It is also known to use rubber rollers as cam followers. Rubber rollers are fairly resilient but tend to take a set or assume a different shape when subjected to constant forces. Furthermore, rubber rollers have relatively low abrasion resistance.
Attention is directed to Soder U.S. Pat. No. 2,906,251, issued Sept. 29, 1959, which discloses an engine apparatus including a cam fixed to a timer plate, and a cam follower operably attached to a throttle valve, the cam follower including a roller biased against the cam.